Bathymetry. The bathymetry and shoreline are very simple, and fine
bathymetric resolution is not required. A grid spacing (DXINC) of 200 m is
selected, with 101 cells in the cross-shore (NI) and 51 cells in the alongshore
(NJ). To simplify the input file for this example, the bay is assumed to have
vertical walls on its north, south, and west shores and a 1:100 slope on the
eastern shore. The depth in all grid cells along the entire grid boundary is set to -
1 for land. The first two grid rows (J = 51 and J = 50) of the depth file are given
as follows:
101
51
200.
1.
1.
1. 1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1. 1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1. 1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1. 1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1. 1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1. 1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1. 1.
1.
1.
15.
15. 15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15. 15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15. 15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15. 15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15. 15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
15. 15.
15.
15.
15.
15.
15.
15.
15.
15.
15.
13.
11.
9.
7.
5.
3. 1.
1.
The full depth file would repeat the second series for rows J = 49 through 2, and
the depths for row J = 1 would again all be -1., identical to the first series in the
file. Note that the first line in the depth file represents the northern edge of the
grid (J = NJ), reading from west to east (I = 1,NI), and the last series in the files
would be the southern edge of the grid (J = 1).
Incident wave spectrum. Twenty frequency bins are used with an initial
frequency of 0.04 Hz and a frequency increment of 0.04 Hz. This coarse
frequency resolution is sufficient because, even at high wind speeds, the 20-km
fetch will limit peak wave periods to approximately 5 to 6 sec. The input
spectrum is very simple for this example case. Because the bay is treated as an
enclosed basin, the spectrum on the "offshore" boundary (the western land
boundary for this case) is zero. The input spectrum includes the header with the
date and wind information, followed by 700 zeros (20 frequencies by 35
directions). For a date identifier of 980923, a wind speed of 20 m/sec, a wind
direction of 0 deg relative to the STWAVE grid (wind blowing from the west, for
this example), a peak frequency of 0.8 Hz (set to the highest frequency because
there is no energy in the input spectrum), and 0.0 m water elevation correction;
the beginning of the spectrum file is given by:
20 35
0.04 0.08 0.12 0.16 0.20 0.24 0.28 0.32 0.36 0.40
0.44 0.48 0.52 0.56 0.60 0.64 0.68 0.72 0.76 0.80
980923 20. 0. 0.8 0.
In the input file, these lines would be followed by 700 zeros (35 directions by
20 frequencies) to represent an incident spectrum with no energy.
56
Chapter 6 Example Applications
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